The DENORMS Round Robin test: Measurement procedure and post-processing of time data

The DENORMS Round Robin Test (RRT) is intended to study and improve the techniques used for the determination of the sound absorption coefficient of materials, with particular focus on the low-frequency range and on measurements in reverberation rooms. It is well known that the main reason why it is difficult to extend the frequency range of interest below 100 Hz is the low modal density. The modal behavior of a room is dependent on its geometry and this is one of the reasons why a discrepancy of the results coming from different laboratories can be found even if the same material is tested. This paper describes the measurement procedure developed to allow uniform acquisition and post-processing of acoustic response data of laboratories participating in the RRT, with and without absorbing materials inside. The tests and the post-processing operations performed on the measured data are also discussed in the paper

Principles at the basis of the denorms round robin test on the low frequency sound absorption measurements in reverberation rooms and impedance tube

In recent years low frequency measurements in building and room acoustics fields gained attention. Moreover the low frequency sound absorption coefficient (below 100 Hz) has always been difficult to determine and the results coming from different laboratories cannot always be compared. This paper describes the principles at the basis of the round robin test carried out in the framework of the DENORMS cost action (Designs for Noise Reducing Materials and Structures). The same samples have been measured in reverberation rooms and in impedance tube by the different laboratories participating to the Round Robin Test.status: accepte

Impedance tube measurements on the denorms round robin test material samples

The DENORMS Round Robin Test aims to study and improve the techniques used to determine the sound absorption coefficient of materials. Within this framework, samples taken from the same batch have been tested in both reverberation room and impedance tube. The latter technique presents some challenges in that the results may strongly depend on the specimen preparation and set-up. The purpose of this paper is to present the results obtained in custom-made impedance tube for the RRT set of materials. The tests have been carried out using a four-microphone impedance tube, according to the method outlined in the ASTM E2611-09 standard. The results obtained for the different parameters provided by the test, in particular the sound absorption coefficient and the sound transmission loss, are taken into account and discussed

Future oriented group training for suicidal patients: a randomized clinical trial

<p>Abstract</p> <p>Background</p> <p>In routine psychiatric treatment most clinicians inquire about indicators of suicide risk, but once the risk is assessed not many clinicians systematically focus on suicidal thoughts. This may reflect a commonly held opinion that once the depressive or anxious symptoms are effectively treated the suicidal symptoms will wane. Consequently, many clients with suicidal thoughts do not receive systematic treatment of their suicidal thinking. There are many indications that specific attention to suicidal thinking is necessary to effectively decrease the intensity and recurrence of suicidal thinking. We therefore developed a group training for patients with suicidal thoughts that is easy to apply in clinical settings as an addition to regular treatment and that explicitly focuses on suicidal thinking. We hypothesize that such an additional training will decrease the frequency and intensity of suicidal thinking.</p> <p>We based the training on cognitive behavioural approaches of hopelessness, worrying, and future perspectives, given the theories of Beck, McLeod and others, concerning the lack of positive expectations characteristic for many suicidal patients. In collaboration with each participant in the training individual positive future possibilities and goals were challenged.</p> <p>Methods/Design</p> <p>We evaluate the effects of our program on suicide ideation (primary outcome measure). The study is conducted in a regular treatment setting with regular inpatients and outpatients representative for Dutch psychiatric treatment settings. The design is a RCT with two arms: TAU (Treatment as Usual) versus TAU plus the training. Follow up measurements are taken 12 months after the first assessment.</p> <p>Discussion</p> <p>There is a need for research on the effectiveness of interventions in suicidology, especially RCT's. In our treatment program we combine aspects and interventions that have been proven to be useful in the treatment of suicidal thinking and behavior.</p> <p>Trial registration</p> <p>ISRCTN56421759</p

Stress and its influence on reproduction in pigs: a review

The manifestations of stress, defined as a biological response to an event that the individual perceives as a threat to its homeostasis, are commonly linked to enhanced activity of the hypothalamo-pituitary-adrenal (HPA) axis and the activation of the sympathetic adreno-medullary (SA) system. Activation of the HPA system results in the secretion of peptides from the hypothalamus, principally corticotropin releasing hormone (CRH), which stimulates the release of adrenocorticotropic hormone (ACTH) and beta-endorphin. ACTH induces the secretion of corticosteroids from the adrenal cortex, which can be seen in pigs exposed to acute physical and/or psychological stressors. The present paper is a review of studies on the influence of stressors on reproduction in pigs. The effects of stress on reproduction depend on the critical timing of stress, the genetic predisposition to stress, and the type of stress. The effect of stress on reproduction is also influenced by the duration of the responses induced by various stressors. Prolonged or chronic stress usually results in inhibition of reproduction, while the effects of transient or acute stress in certain cases is stimulatory (e.g. anoestrus), but in most cases is of impairment for reproduction. Most sensitive of the reproductive process are ovulation, expression of sexual behaviour and implantation of the embryo, since they are directly controlled by the neuroendocrine system

Who decides what is fair in fair trade? The agri-environmental governance of standards, access, and price

The agri-environmental governance of value chains can favour a Polanyian double movement seeking social protection and control over price setting markets or it can advance a neoliberal logic that strives to overcome the few remaining civic and ecologic obstacles to full market dominance. Coupled with a typology that contrasts corporate social responsibility and social economy Fair Trade models, this theoretical framework elucidates positions in the current policy debates about the minimum coffee price standard. Many Southern smallholders consider Fair Trade's standards, which for coffee include direct market accesses for smallholder cooperatives, minimum prices, and environmental criteria, among the best deals available. The smallholder empowerment benefits are often better than competing eco-labels. However, this study finds that Fair Trade minimum prices lost 41 percent of their real value from 1988 to 2008. Despite objections from several 'market driven' firms and national labelling initiatives, smallholders' collective advocacy and this research contributed to the Fairtrade Labelling Organisations International's (FLO) decision to mandate a 7-11 percent minimum price increase. The price debates demonstrate that Fair Trade governance is neither purely neoliberal nor social movement led - it is a highly contested socially embedded practice. Voices without votes, North-South inequalities, and dwindling prices paid to its stated protagonists indicate the need for governance reform, cost of living price adjustments, and additional investment in the innovative alternative trade and hybrid models

Being lonely or using substances with friends? A cross-sectional study of Hungarian adolescents’ health risk behaviours

BACKGROUND: Studying adolescents' health risk behaviours is oddly significant in Central and Eastern European countries, where the prevalence of smoking and drinking among 14-18 year old students is significantly high. The goal of our study is to examine the role of social psychological and social behavioural variables in health risk behaviours among Hungarian adolescents. METHODS: Our sample was comprised of three high schools of Debrecen (the second largest city of Hungary). In all, 501 students filled in the questionnaire from 22 classes (14-22 years old). Students aged above 18 years were excluded for the purpose of the study, giving a total sample size of 471 high school students. Descriptive statistics and binary logistic regression analyses were conducted. RESULTS: According to our results (1) social behavioural factors (namely, smoking and alcohol use of the best friend and peer group) proved to be better predictors of adolescents' health risk behaviours as compared to the included social psychological attributes (2); among the latter ones, loneliness and shyness were negatively related with both smoking and drinking, while competitiveness was a predictor of drinking prevalence among boys. CONCLUSIONS: The findings suggest that social behavioural factors, including smoking and drinking of friends, are oddly important predictors of Hungarian adolescents' health risk behaviours. According to our results, health policy should pay more attention to peer norms related to smoking and drinking during school health promotion. Developing health protective social norms may be an indispensable component of effective health promotion in high schools

Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease

BACKGROUND: Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes. METHODS: We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization. RESULTS: During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events. CONCLUSIONS: Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)

Characterization of elastic parameters of point and line excited porous materials by means of the wave correlation method, Hankel functions and Mindlin’s plate theory; a numerical study

This paper reports on the characterization of the mechanical properties of a point excited and line excited porous material by means of the inhomogeneous wave correlation approach based on the Hankel's function. The correlation approach allows the wavenumber to be complex. Both propagating waves and evanescent waves are considered. Excitation along a line is approximated by means of an array of points. First order reections from the edges are taken into account by mirror images. The material properties, in terms of Young's modulus and loss factor, are estimated by means of Mindlin's plate theory. The obtained results are compared with Kirchho's thin shell theory and Lamb wave theory. A numerical model was used to simulate measurements on a porous sample. Knowing the material properties a priori (i.e. the properties that were used as input to the numerical simulation), opened the possibility to check the correctness of the characterization procedure and zoom in on possible deviations. It was found that at higher frequencies and thicker slabs Kirchho's thin shell theory is clearly insucient. It was also found that for the frequency range and thicknesses studied, Mindlin's plate theory and Lamb wave theory are not very much dierent (error in wavenumber less than 2% for frequencies up to 1000 Hz and thicknesses up to 10 mm). Good results were obtained for the Young's modulus and the loss factor of the slab material by considering evanescent waves and reections from the edges of the slab by means of mirror images, using Mindlin's thick plate theory. Taking into account the rst order reection seems sucient for the type of slab and frequencies considered